The purpose of this study was to investigate the relationships among obesity, physical fitness and exercising habit in 162 male and 18 female factory workers. Obesity was measured by body length, body weight, body fatness, and the waist to hip ratio (WHR). Physical fitness consisted of grip strength, standing trunk flexion, foot balance with closed eyes, vertical jump, whole body reaction time and breath holding time. Exercising habit was investigated with the questionnaire. A positive correlation was found between WHR and body fatness (male: r = 0.55, p<0.01, female: r = 0.74, p<0.01). The WHR of male was correlated with age (r = 0.61, p<0.01). There were partial correlation between WHR and the result of grip strength test (r = 0.16, p<0.05) and between WHR and the result of vertical jump test (r = -0.14, p<0.1) in male. The WHR of female was not correlated with the results of all 6 parameters of physical fitness. There was the only significant difference between exercising habit group and non exercising habit group in the result of vertical jump of female (p<0.05). On the other hand, there was no relationship between exercising habit group and non exercising habit group in WHR. The findings of this study could not solve sufficiently relationships among obesity, physical fitness and exercising habit. However, they suggest that obesity and exercising habit might affect the physical fitness, so that workers need more proper instructions about obesity, physical fitness and exercising habit to keep their good health.